Skip to
  1. Homepage
  2. Rare diseases
  3. Search
Simple search

Simple search

(*) mandatory field


Other search option(s)

Giant cell arteritis

Synonym(s) Horton disease
Temporal arteritis
Prevalence 1-5 / 10 000
Inheritance Multigenic/multifactorial
Age of onset Adult
  • M31.6
  • C0039483
  • C1956391
  • D013700
  • 10018250
  • 10043207


Disease definition

Giant cell arteritis (GCA) is a large vessel vasculitis predominantly involving the arteries originating from the aortic arch and especially the extracranial branches of the carotid arteries.


GCA is the most common adulthood vasculitis with an annual incidence of 1/3,000-1/25,000 adults over 50 years old. It is more frequent in populations of northern European background. GCA affects people of more than 50 years old (median age at diagnosis between 70-75 years old) and occurs twice as frequently in women as in men.

Clinical description

GCA often starts insidiously with general symptoms, cranial manifestations (headache, jaw claudication, scalp tenderness, visual loss), and, in about 50% of patients, polymyalgia rheumatica. Visual symptoms due to an ischemic optic neuropathy occur in 20-30% of patients, and can rapidly lead to irreversible monocular blindness. Large artery disease, including carotid or subclavian arteries, may also occur. Thoracic aortitis with aneurysms occur in approximately 15% of patients but are generally a late complication of GCA.


The etiology of giant cell arteritis is unknown. Studies have linked genetic factors, infectious agents and a prior history of cardiovascular disease to the development of giant cell arteritis.

Diagnostic methods

The diagnosis of GCA can be made by a temporal artery biopsy or based on the association of demographic features (age > 50 years), clinical criteria (cranial symptoms), elevated inflammatory markers, and a favorable response to glucocorticoids. In temporal artery biopsy, the most important (and mandatory) histological criterion for the diagnosis of GCA is a mononuclear cell infiltrate predominating at the media-intima junction or involving the entire vessel wall (panarteritis). The potential role of imaging studies in the assessment of giant-cell arteritis (e.g., ultrasonography or MRI of the temporal arteries, F18 PET scan) has received increasing attention but it remains uncertain how they should best be integrated into the diagnostic workup.

Differential diagnosis

In elderly patients presenting with general symptoms and elevated inflammatory markers, diagnoses of cancer or infection need to be considered. Symptoms of polymyalgia rheumatica can also point towards diagnoses of isolated polymyalgia rheumatica or rheumatoid arthritis. In some instances, biopsy-proven involvement of the temporal arteries can be seen in other systemic vasculitides, e.g., polyarteritis nodosa or microscopic polyangiitis.

Management and treatment

Glucocorticoids are highly and rapidly effective in GCA but are often associated with substantial morbidity in an elderly population. Adjunctive immunosuppressive agents, e.g. methotrexate, have been considered to allow reduction in use of glucocorticoids. Concomitant prescription of antiplatelet or anticoagulant therapy was suggested to reduce the occurrence of ischemic events in giant cell arteritis.


The disease is chronic and the clinical course is highly variable. Approximately 50% of patients experience subsequent disease flares. Visual loss is the most feared complication.

Expert reviewer(s)

  • Dr Alfred MAHR

(*) Required fields.

Attention: Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Captcha image

Detailed information

Article for general public
Get Acrobat Reader
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.